Simone
exercise表示锻炼时，为不可数名词，例如take exercise锻炼身体、vigorous exercise剧烈运动等；当exercise表示体操或练习题时是可数名词，要用复数形式exercises，例如do eye exercises做眼保健操、grammar exercises语法练习等。此外exercise还可作动词，其意思是行使、训练、使用、运用、操练、锻炼。
相关例句：1、You are probably well enough to take a little light exercise.
你恢复得不错，大概可以做些轻微的运动了。
2、I don't get much exercise sitting in the office all day.
我整天坐在办公室很少运动。
3、This exercise will work the muscles of the lower back.
这样的运动可以锻炼腰部的肌肉。
4、For maximum effect do the exercises every day.
每天锻炼以取得最佳效果。
5、Each exercise focuses on a different grammar point.
每个练习各有不同的语法重点。
